A sample method to generate a reset token using RNGCryptoServiceProvider instead of a GUID.

RNGCryptoServiceProvider_Randomized_Reset_Token.cs

public string GenerateResetToken(int length)
{
    using (var rng = new RNGCryptoServiceProvider())
    {
        var bytes = new byte[256];

        rng.GetBytes(bytes);

        var str = Convert.ToBase64String(bytes);

        var rgx = new Regex("[^a-zA-Z0-9]");
        str = rgx.Replace(str, "");

        return str.Substring(0, length);
    }
}